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Non-Gaussianity in Curvaton Models with Nearly Quadratic Potential

Kari Enqvist·Sami Nurmi
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Abstract

We consider curvaton models with potentials that depart slightly from the quadratic form. We show that although such a small departure does not modify significantly the Gaussian part of the curvature perturbation, it can have a pronounced effect on the level of non-Gaussianity. We find that unlike in the quadratic case, the limit of small non-Gaussianity, $|f_{NL}|\ll1$, is quite possible even with small curvaton energy density $r\ll1$ . Furthermore, non-Gaussianity does not imply any strict bounds on $r$ but the bounds depend on the assumptions about the higher order terms in the curvaton potential.

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Kari Enqvist, Sami Nurmi. 2005-09-06. Non-Gaussianity in Curvaton Models with Nearly Quadratic Potential. https://doi.org/10.1088/1475-7516%2F2005%2F10%2F013

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